Square gemstone



FIG. 1 is a top plan view of a square gemstone according to the design of my invention;

FIG. 2 is a side elevational view thereof, the opposite side being a mirror image;

FIG. 3 is a front elevational view thereof, the rear elevational view being a mirror image; and,

FIG. 4 is a bottom plan view thereof. 

The ornamental design for a square gemstone, as shown and described. 